• Journal of Korean Tunnelling and Underground Space Association
• /
• v.10 no.3
• /
• pp.269-282
• /
• 2008

In general, the effects of steel ribs are not considered in the numerical analysis of tunnel design. However, attempts have been increased recently to consider these effects in the analysis of shallow tunnels in soft ground, based on the fact that the steel ribs embedded in the shotcrete take a role to support some portion of the redistributed load due to excavation. In such analyses, the steel ribs can be considered in four different methods: (1) a conventional method where the steel ribs are not considered, (2) a method using the equivalent composite cross section in which the bending moment of shotcrete is not considered, (3) a method using the equivalent composite cross section in which both the compressive stress and the bending moment for the shotcrete and steel rib are considered, and (4) a method using beam elements for the shotcrete and the steel rib, respectively. These methods are adopted in the numerical analysis using FLAC 2D to investigate stresses of both the shotcrete and the steel rib. The overall results show that the analyses are more practical and economical when the effects of steel rib are considered fer the methods (2), (3), and (4). Since the results of those analyses considering steel rib capacity may be different according to the ground condition, it will be necessary to consider the appropriate method among them in accordance with design conditions.

• Communications of the Korean Mathematical Society
• /
• v.29 no.3
• /
• pp.409-413
• /
• 2014

In this paper, we study some quantity equivalent to the norm of Bloch to $A^p_{\alpha}$ composition operator where Ap $A^p_{\alpha}$ is the weighted Bergman space on the unit ball of $\mathbb{C}^n$ (0 < p < ${\infty}$ and -1 < ${\alpha}$ < ${\infty}$).

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 1998.04a
• /
• pp.77-84
• /
• 1998

The finite strip method is presented for the analysis of steel deck bridges. Like the Pelikan-Esslinger design method for the steel deck bridges, steel deck is treated as an equivalent orthotropic plate. In the presented method, the deck is discretised by finite strips in the longitudinal direction and the effect of main girder or floor beam deflection can also be accounted for. In this method, the terms of harmonic series at elastically support such as transverse floor or diaphragm in steel deck become coupled. Solutions of this method are compared with other available analytical and numerical solution, and good agreement is observed.

• The Journal of Society for e-Business Studies
• /
• v.4 no.1
• /
• pp.103-115
• /
• 1999

The electronic cash, an electronic equivalent of the real paper money, has been recently proposed as one of the various payment methods for electronic commerce. In this paper, we design an electronic cash payment system based on a new electronic cash payment protocol that can effectively provide full anonymity and avoid double-spending. The protocol is suitable for use as the electronic cash control or electronic cash database. The protocol support also security and electronic cash property.

• Nonlinear Functional Analysis and Applications
• /
• v.27 no.4
• /
• pp.785-795
• /
• 2022

In this paper, we introduce a Mann-like three step iteration method and show that it can be used to approximate the fixed point of a weak contraction mapping. Furthermore, we prove that this scheme is equivalent to the Mann iterative scheme. A comparison is made with the other third order iterative methods. Results are presented in a table to support our conclusion.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.10b
• /
• pp.703-705
• /
• 2004

Conventional support vector machines (SVMs) find optimal hyperplanes that have maximal margins by treating all data equivalently. In the real world, however, the data within a data set may differ in degree of uncertainty or importance due to noise, inaccuracies or missing values in the data. Hence, if all data are treated as equivalent, without considering such differences, the optimal hyperplanes identified are likely to be less optimal. In this paper, to more accurately identify the optimal hyperplane in a given uncertain data set, we propose a membership-induced distance from a hyperplane using membership values, and formulate three kinds of membership-induced SVMs.

• Proceedings of the KSR Conference
• /
• 2004.06a
• /
• pp.1065-1070
• /
• 2004

When the track designer analyze the track structure uses many known & unknown parameters. Unknown parameters, equivalent rail support spring factor, unit rail support spring factor, track damping coefficient, should be assumed. Known parameters are section properties (area, section factor, etc), material properties(modulus of elasticity, mass, etc) and track conditions(wheel load, loading conditions, gauge, etc.). In the assumption of track design parameters, some parameters can be overestimated or under estimated. The purpose of this study is to verify design parameters used in track design, in the way of experimental measurements. Data of displacements, banding stresses, loads, accelerations are measurable at track site. From these data, unknown parameters are derived. Compare these assumed and derived parameters, estimate the entire track stability.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.14 no.3
• /
• pp.92-98
• /
• 2015

This study investigates the durability of a two-passenger bicycle frame under non-uniform fatigue load. The bicycle frame of Model 1 installed with reinforcement support has a 20% lower maximum equivalent stress than the existing Model 2. Model 1 has a maximum total deformation that is less than half that of Model 2. Model 1 has a higher maximum fatigue life than Model 2. In addition, Model 1 has lower fatigue damage than Model 2. Thus, the bicycle frame of Model 1 installed with reinforcement support can be described as safer, as it offers more strength than Model 2. Applying this result to the design of a real two-passenger bicycle frame under non-uniform fatigue load can effectively prevent fatigue damage and improve durability.

• Korean Journal of Child Studies
• /
• v.15 no.1
• /
• pp.23-35
• /
• 1994

This paper investigated children's learning process concerning age and gender, two of the most apparent social roles. The subjects of the study were 72 Korean preschool children between three to five years of age. The Study was designed to examine problems of developmental sequence and horizontal decalage in understanding of these social roles. Two five-step knowledge sequences of age growth and sex constancy were administered utilizing skill theory (Fischer, 1980). Each step in a sequence had different stories of age or sex role with increasing cognitive complexity, but the two sequences were equivalent in complexity. The children were tested under two different assessment conditions:high support condition of elicited imitation and low support condition of free play and the best story. The findings show that, the understanding of age and sex roles develops through the predicted five-step sequences. The understanding of age role seems to develop earlier than that of sex role although the developmental patterns of the two roles are similar. Variations in the children's performances under different conditions were dramatic, especially for the older children.

• Journal of the Korean Society of Safety
• /
• v.32 no.1
• /
• pp.60-65
• /
• 2017

In this study, a simplified FE model for evaluating seismic performance of valve support was suggested and an apparatus for a real structure testing was developed. The seismic performances of three different types of valve supports were evaluated by the real structure testing. By comparing the results between the real structure testing and FEA using the simplified FE model, it was verified that the suggested simplified FE model can be utilized for comparative evaluation of seismic performance of valve supports.